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Espionage is happening now in Aust: ASIO

Australia's domestic intelligence agency claims existing laws are limiting its ability to properly deal with spies and the "extreme" threat of foreign interference.

Deputy Director-General of ASIO, Heather Cook, on Friday warned that Australia's interests were being harmed "as we speak" and more tools were needed to fill some gaps.

"Foreign interference is taking place in Australia," she told a parliamentary inquiry.

"Espionage and foreign interference activity against Australian interests is extensive, unrelenting and increasingly sophisticated."

She said foreign powers are out to gain advantage for themselves or to disadvantage Australia, and want information on intelligence and defence capabilities, as well as industry and alliance relationships.

ASIO is asking the federal government to extend special powers to coercively question people on all elements of security.

As it stands, it can only apply for such a warrant if it relates to a terrorism offence.

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While terrorism consumes most of the organisation's time because of the immediacy and threat to life, espionage is an extreme threat and occurring right now.

"The fact that we don't have it open to us under our current legislative regime to be able to use a power such as compulsive questioning in the espionage and foreign interference space is definitely a limitation," she said.

"We believe with that authority, we would be able to resolve some of those issues more quickly."

The agency also wants to speed up the process of obtaining a warrant, allowing for verbal authorisation from the attorney-general - rather than written - in emergency situations.

In addition, it wants the ability to search people subject to the warrants and lower the minimum age for compulsory questioning from 16 to 14.

The powers, introduced in 2003 following the September 11 attacks and Bali bombings, are under review by a parliamentary committee before they expire in September 2018.

She warned about the need to consider the implications of expanding them.

"Every step taken to extend the ambit of those powers would have to be carefully thought about," the former Federal Court judge said.

"The question would be: What is it they are wanting to find out that they can't find out without these powers?"

Ms Stone says removing any safeguards would be a matter of "real concern", questioning what would be gained as a result.

"If you take away any of these safeguards, you lose something."

The Independent National Security Legislation Monitor in February called for the power to detain and question people to be repealed immediately, believing it was not appropriate to the threat of terrorism.

Former judge Roger Gyles QC recommended replacing it with a questioning power available under the Australian Crime Commission Act.

ASIO has never formally sought to detain and question someone under the regime, and only once since 2006 used its power to compulsory questioning a person.

But it wants to retain the ability, arguing its removal would be a "loss".